New PROVENGE® (sipuleucel-T) Data to Be
Presented at 2013 American Society of Clinical Oncology (ASCO)
Genitourinary Cancers Symposium

-- Two studies examine potential for PROVENGE in combination or
sequenced with two approved advanced prostate cancer therapies

-- Additional retrospective study data suggest that relative to
placebo, PROVENGE may delay time to first opioid use for pain in
patients with advanced prostate cancer

-- Preliminary data on NeuACT study for high-risk urothelial
carcinoma show high frequency of HER2 expression at primary tumor and
lymph node samples

February 13, 2013 08:03 AM Eastern Time

BRIDGEWATER, N.J.--(BUSINESS WIRE)--February 13, 2013--Dendreon Corporation (NASDAQ: DNDN)
today announced that results from several ongoing or completed studies
investigating the utility of PROVENGE®(sipuleucel-T)in the treatment of advanced prostate cancer, including studies that
may lead to new treatment approaches, as well as the investigational
immunotherapy DN24-02 in patients with surgically-resected urothelial
cancer, will be presented at the 2013 American Society of Clinical
Oncology (ASCO) Genitourinary Cancers Symposium in Orlando, Florida,
from February 14-16, 2013.

“The
studies that inform us about the potential use of PROVENGE in
combination or sequenced with other advanced prostate cancer treatments
are encouraging, and we look forward to additional data from these
studies.”

“This year’s ASCO GU meeting is important for Dendreon because of the
wide range of studies being presented that help us better understand
PROVENGE,” said Mark Frohlich, M.D., executive vice president of
research and development and chief medical officer at Dendreon. “The
studies that inform us about the potential use of PROVENGE in
combination or sequenced with other advanced prostate cancer treatments
are encouraging, and we look forward to additional data from these
studies.”

“These preliminary PROVENGE data are promising for the treatment of
metastatic castrate resistant prostate cancer," said Eric Small, M.D.,
Chief of the Division of Hematology and Oncology, and Deputy Director,
UCSF Helen Diller Family Comprehensive Cancer Center. “The medical
community is particularly excited about the studies investigating the
potential for treatment with PROVENGE and other currently approved
treatments for advanced prostate cancer, which may provide us with new
therapeutic approaches to help men fight this disease in the future.”

Additional Dendreon abstracts accepted for presentation at the meeting
can be accessed via the following links:

PROVENGE is intended solely for autologous use and is not routinely
tested for transmissible infectious diseases.

The safety evaluation of PROVENGE was based on 601 prostate cancer
patients in four randomized clinical trials who underwent at least one
leukapheresis. The most common adverse events (incidence greater-than or
equal to 15%) are chills, fatigue, fever, back pain, nausea, joint ache,
and headache. Serious adverse events reported in the PROVENGE group
include acute infusion reactions (occurring within 1 day of infusion)
and cerebrovascular events. In controlled clinical trials, severe (Grade
3) acute infusion reactions were reported in 3.5% of patients in the
PROVENGE group. Reactions included chills, fever, fatigue, asthenia,
dyspnea, hypoxia, bronchospasm, dizziness, headache, hypertension,
muscle ache, nausea, and vomiting. No Grade 4 or 5 acute infusion
reactions were reported in patients in the PROVENGE group.

To fulfill a post marketing requirement and as a part of the company's
ongoing commitment to patients, Dendreon will conduct a registry of
approximately 1500 patients to further evaluate a small potential safety
signal of cerebrovascular events. In four randomized clinical trials of
PROVENGE in prostate cancer patients, cerebrovascular events were
observed in 3.5% of patients in the PROVENGE group compared with 2.6% of
patients in the control group.

Dendreon Corporation is a biotechnology company whose mission is to
target cancer and transform lives through the discovery, development,
commercialization and manufacturing of novel therapeutics. The Company
applies its expertise in antigen identification, engineering and cell
processing to produce active cellular immunotherapy (ACI) product
candidates designed to stimulate an immune response in a variety of
tumor types. Dendreon's first product, PROVENGE®
(sipuleucel-T), was approved by the FDA in April 2010. Dendreon is
exploring the application of additional ACI product candidates and small
molecules for the potential treatment of a variety of cancers. The
Company is headquartered in Seattle, Washington and is traded on
the NASDAQ Global Market under the symbol DNDN. For more information
about the Company and its programs, visit http://www.dendreon.com.

Statements in this press release that are not strictly historical in
nature constitute “forward-looking statements.” Such statements include,
but are not limited to, statements regarding the expected benefits of
the restructuring, the timing and elements of the restructuring, the
timing and form of related charges, the expected annual operating
expense reduction, expectations and beliefs regarding Dendreon’s
profitability and Dendreon’s ability to achieve improved performance as
a result of the restructuring, expectations regarding regulatory
approval of PROVENGE® in Europe, expectations
regarding the presentation of clinical data, developments affecting
Dendreon's U.S. and global business and prospects and potential revenue
and earnings from product sales, expectations regarding market size and
market opportunity, and progress generally on commercialization efforts
for PROVENGE. Such forward-looking statements involve known and unknown
risks, uncertainties and other factors which may cause Dendreon’s actual
results to be materially different from historical results or from any
results expressed or implied by such forward-looking statements. These
factors include, but are not limited to, our inability to achieve and
sustain commercial success for PROVENGE; the identification of efficacy,
safety or other issues with PROVENGE; a slower than anticipated adoption
by treating physicians of PROVENGE for the treatment of patients with
advanced prostate cancer due to competing therapies, perceived
difficulties in the treatment process, delays in obtaining reimbursement
or for other reasons; any promotional limitations imposed by the FDA on
our ability to commercialize and market PROVENGE; unexpected
difficulties and costs associated with the rapid expansion of our
operations to support the commercial launch of PROVENGE; and other
factors discussed in the “Risk Factors” section of Dendreon’s Quarterly
Report on Form 10-Q for the quarter ended September 30, 2012. All
forward-looking statements are qualified in their entirety by this
cautionary statement. Dendreon is providing this information as of the
date of this press release and does not undertake any obligation to
update any forward-looking statements contained in this release as a
result of new information, future events or otherwise.

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